Semester 2 Final Review Part 2

Carbohydrates, Photosynthesis & Respiration and Ecology

Biomes & Biodiversity

BiomesEarth is covered by many types of ecosystems.Ecologists group these ecosystems into larger

areas known as biomes.

Biome: a large region characterized by a specific type of climate and certain types of plant and animal communities.

Thus biomes are made up of smaller ecosystems.

BiomesBiomes are described by their vegetation

because the plants are the most noticeable characteristics of that region.

Organisms that depend on those plants live where the plants are and so on.

The term biodiversity, short for “biological diversity,” usually refers to the number of different species in a

given area. Certain areas of the planet, such as tropical rain forests,

contain an extraordinary variety of species, and thus have a high biodiversity. Other areas, like deserts have

relatively little life, and thus low biodiversity.

Ecology

The study of the interactions of living organisms with one another and their physical environment.

Levels of Organization in Biology

Atom Molecule Cell Tissue Organ System

Organism Population Community Ecosystem Biosphere

ECOLOGY

Ecosystem A community

(many different species) that live together in a habitat

and the habitat

Ecosystem The physical boundaries are

not always obvious (no location is ever totally isolated from other places) Organisms can

participate in two ecosystems at the same time.

Ex. Canada Geese have a breeding range that stretches from Alaska to northern Florida.

This range includes everything from tundra to temperate forests.

Biotic vs Abiotic: Biotic-All the LIVING components of an ecosystem

The community of organisms Abiotic factors-All the non-living components of an

ecosystem Affect balance of food web Determines who can live in a specific habitat Examples:

Amount of rain Temperature Amount of nutrients in soil Pollutants

HABITAT:

the place where a particular population lives

COMMUNITY All the interacting organisms

(many different species) living in an area.

Community Interactions Predation : + / - Parasitism: +/ - Commensalism: + / 0 Mutualism: + / +

Whale with barnacles on skin

Bat about to eat frog

Mistletoe growing into a mangrove tree

Bee pollinating flower

POPULATION: All the members of one species that live in one place

at one time.

The Flow of Energy in an Ecosystem

Food Chain: Describes feeding relationships and the path of energy through food consumption

The Flow of Energy in an Ecosystem All ENERGY flows into ecosystem from the

SUN (except in thermal vents in the ocean). Photosynthesis makes it possible to capture light

energy from sun and transform it into chemical energy of organic molecules (food).

All organisms are chemical machines driven by energy captured in photosynthesis.

How does a food chain work?

It is based on which organism is eaten by which other organism

The arrow always points to the animal doing the eatingIn the direction of the flow of energy

TROPHIC LEVELS Determined by the organism’s source of

energy1. Autotrophs2. Heterotrophs3. Saprotrophs

1. AUTOTROPHS: Capture energy from the sun

(photosynthetic) or inorganic molecules = chemicals (chemosynthetic) and converts it into usable energy.

Also known as PRODUCERS produces food (make energy storing molecules),

Ex. Plants, algae and some kinds of bacteria

2. HETEROTROPHS- cannot capture energy from the sun and

must eat autotrophs to get energy. Herbivores: Plant eaters Carnivores: Eat animals Omnivores: Eat plants and animals Scavengers: Eat dead organisms

2. HETERTROPHS- CONSUMER

obtains the energy to build their molecules by consuming plants or other organisms

PRIMARY (1st Order) CONSUMER (herbivores)-

eats producerEx. Cows, horses, caterpillars and ducks

Secondary (2nd Order) CONSUMER (carnivores)-

eats herbivores Carnivore

Ex. Wolf, ferret, and leopard

SECONDARY (2nd ORDER) CONSUMER eats 1st order

CarnivoreEx. Tigers,

wolves and snakes

OmnivoreEx. Bears,

humans

TERTIARY (3rd ORDER) CONSUMER-

eats second order (other carnivores)Ex. Hawk

QUATERNARY (4th ORDER) CONSUMER this is very rare…

Not enough energy at the level before to support these higher levels Ex. Orca